Apparatus for false-twisting yarn

ABSTRACT

A bush twister for false-twisting yarn is of the known kind comprising a friction bush at each end of a bush tube of comparitively large diameter, the yarn being false-twisted by running it through the bore of the bush twister, which is not supported in anti-friction bearings but is supported and driven by engagement with the rim of a driving wheel, against which the bush twister is held by a pair of idler wheels on a pivotal spring-loaded arm.

United States Patent [1 1 Naylor et a1.v

[11] 3,753,343 [451 Aug. 211, 1973 1 APPARATUS FOR FALSE-TWISTING YARN[75] Inventors: Geoffrey Naylor; Harold Sydney a Messlssfisldifi L [73]Assignee: Ernest Scragg & Sons Limited,

Macclesfield, Cheshire, England [22] Filed: Jan. 19, 1972 [2]] Appl.No.: 219,026

[52] Cl. 57/77.45 [51] int. Cl D02g 1/04, D02g 1/06 [58] Field of,Search 57/77.3, 77.4, 77.45

[56] References Cited UNITED STATES PATENTS 4/1972 Kuussaari 57/77.45 X4/1960 Haas 57/77.45 X

FOREIGN PATENTS OR APPLICATIONS Great Britain 57/77.45

848,971 9/1960 Great Britain 57/77.45 932,206 7/1963 Great Britain57/77.45 1,023,951 3/1966 Great Britain 57/77.45

Primary Examiner-Donald E. Watkins AttorneyMichael S. Striker [5 7]ABSTRACT A bush twister for false-twisting yarn is of the known kindcomprising a friction bush at each end of a bush tube of comparitivelylarge diameter, the yarn being false-twisted by running it through thebore of the bush twister, which is not supported in anti-frictionbearings but is supported and driven by engagement with the rim of adriving wheel, against which the bush twister is held by a pair of idlerwheels on a pivotal spring-loaded arm.

17 Claims, 4 Drawing Figures 1 APPARATUS FOR FALSE-TWISTING YARN Thisinvention relates to apparatus for false-twisting yarn, and of the kindin which a running yarn is falsetwisted by a so-called bush twistercomprising a friction bush or bushes carried by a bush tube ofcomparatively large diameter, through the bore of which the running yarnpasses to be false-twisted by engagement with the friction bush orbushes rotating in a direction transverse to the path of the runningyarn.

Hitherto it has been customary to support the bush twister of this kindin ball bearings or similar antifriction bearings, but at the highspeeds of rotation required of bush twisters of this kind, bearingfailure and lubrication of the bearings becomes a major problem.

According to the present invention, in apparatus of the kind referred toabove, the bush twister is not mounted in anti-friction bearings but issupported and driven by engagement with the periphery of a rotatabledriving wheel, means being provided for holding the bush twister infrictional driving engagement with the periphery of the driving wheel.

The holding means may comprise a pair of wheel members, freely rotatableabout parallel axes, and each wheel member may comprise two discsmounted for rotation about a common axis.

The driving wheel may be mounted on a drive shaft, the axis of rotationof the drive shaft being parallel to the axes of rotation of the wheelmembers and the bush twister. Alternatively the axis of rotation of thedrive shaft may be transverse to the axes of rotation of the wheelmembers and the bush twister.

The wheel members may be rotatably mounted on a common arm which ismounted so as to be pivotable about a fixed axis parallel to the axes ofrotation of the wheel members and the bush twister, and which isresiliently urged in a direction towards the driving wheel.

The driving wheel may have the form of a disc mounted on the drive shaftand lying in a plane normal to the axis of the drive shaft. In this casethe axis of rotation of the drive shaft will be parallel to the axes ofrotation of the wheel members and the bush twister. The driving wheelmay have around its periphery a tyre of a material which is durable andhas good frictional properties. A suitable material for such a tyre ispolyurethane. Alternatively the driving wheel may have the form of acup-like rotor with an axially directed rim carrying a tyre of amaterial which is durable and has good frictional qualities such aspolyurethane. In this case the axis of rotation of the drive shaft willbe transverse to the axes of rotation of the wheel members and the bushtwister. Each disc of the wheel members may also have such a tyre aroundits periphery. Altematively the bush twister may have such a tyre aroundits cylindrical outer surface where it is contacted by the driving wheeland the discs.

The drive shaft may have a pulley mounted thereon and around which theyarn being false twisted can be passed to thereby feed the yarn throughthe spindle.

The bush twister may be located axially by magnetic means situatedadjacent the bush twister in its normal running position and arranged toresist any tendency for the bush twister to move in an axial direction.

The invention will now be described with reference to the accompanyingdrawings in which:

FIG. 1 shows one embodiment of false twisting apparatus according to theinvention.

FIG. 2 shows a sectional view along the line II II of the apparatus ofFIG. 1.

FIG. 3 isa sectional view along the line Ill-III of the apparatus ofFIG. 4, and

FIG. 4- shows an alternative embodiment of false twisting apparatusaccording to the invention.

FIGS. 1 and 2 show a bush twister 26 being driven in rotation by meansof a driving wheel 2. The yarn 3 passes through the bore 4 of the bushtwister 26 and is flase twisted by frictional engagement with the convexsurfaces 5 of friction bushes 6 mounted in the ends of the bore 4. Thebush twister 26 is held in frictional driving contact with theperipheral surface 1 of the driving wheel 2 by means of a pair of wheelmembers 8.

Each wheel member 8 comprises two discs mounted coaxially on a spindle 7which passes through an arm 9 so that each wheel member 8 is freelyrotatable. The arm 9 is pivoted about the fixed axis of shaft 10 so thatit is movable in a plane containing the driving wheel 2 and isresiliently urged towards the driving wheel 2 by means of a coil spring13.

The driving wheel 2 is mounted on a drive shaft 14 having mounted at oneend a pulley 15 around which the yarn 3 is passed thereby being drawnthrough the bush twister 26 and fed to any further processing apparatusor wind-up means (not shown) as required.

The drive shaft 14 runs in a bearing 11 which is mounted on a supportplate 12 on which the shaft 10 is also mounted. A driving pulley 19 ismounted on drive shaft 14 at the opposite end to pulley l5 and is drivenby contact with an endless belt 20, the plane of travel of which ishorizontal. Support plate 12 is secured to the frame 21 of a textilemachine by means of slides 22 which can move in slots 23 in the plate12, the slides 22 being secured to the frame 21 of the machine. Cam 24which may be turned by lever 25 bears against the support plate 12 andthereby lifts the complete apparatus relative to the frame 21 of themachine. This enables the driving pulley 19 to be moved into or out ofdriving engagement with the endless belt 20 as required.

FIGS. 1 and 2 show an embodiment of the apparatus according to theinvention in which the driving wheel 2 and the wheel members 8 haveperipheral tyres l6 and 17 respectively of a material which is durableand has good frictional properties. A suitable material for such a tyreis polyurethane. Alternatively the bush tube 26 may have such a tyrearound its cylindrical outer surface.

A horseshoe magnet 18 is situated adjacent the metal bush twister 26 inits normal running position to resist any tendency for the bush twisterto move axially. Axial movement of the bush twister could bring theflange of one of the friction bushes 6 into contact with at least one ofthe wheel members 8 and there would then be undesirable frictionalcontact between surfaces which are moving at different linear speeds.The magnet 18 is not shown in FIG. 2 for purposes of clarity.

FIGS. 3 and 4 show a bush twister 40 being driven in rotation by meansof a driving wheel 42. Yarn 43 passes through the bore 44 of the bushtwister 40 and is false twisted by frictional engagement with the convexsurfaces 45 of friction bushes 46 mounted in the ends of the bore 44.The bush twister 40 is held in frictional driving contact with theperipheral surface 41 of the driving wheel 42 by means of a pair ofwheel members Each wheel member 48 comprises two discs mounted coaxiallyon a spindle 38 which passes through an arm 37 so that each wheel member48 is freely rotatable. The arm 37 is pivoted about a fixed axis 39parallel to the axes of rotation of the wheel members 48 and the bushtwister 40, and is resiliently urged towards the driving wheel 42 bymeans of a spring 33.

The driving wheel 42 has the form of a cup-like rotor with anaxially-directed rim and is mounted on a drive shaft 34. In theembodiment shown in FIGS. 3 and4 the driving wheel 42 and the wheelmembers 48 have peripheral tyres 36 and 35 respectively of a materialwhich is durable and has good frictional properties, the tyre 36preferably being of crowned or domed crosssectional shape. A suitablematerial for the tyres is polyurethane. Alternatively the bush twister40 may have such a tyre around its cylindrical outer surface.

The cup-like driving wheel 42 is shown as rotating about a vertical axison the shaft 34 which is mounted in a bearing 28. The bearing 28 isitself carried by an arm 29 pivotally mounted for rotation about an axis30 to enable a driving wharve 31 on the shaft 34 to be brought into andout of contact with an endless driving belt 32 the plane of travel ofwhich is vertical.

In the embodiment shown in FIGS. 3 and 4 the bush twister 40 rotatesabout a horizontal axis, and the yarn 43 before and after passingthrough the bush twister is shown to be at a small angle to thevertical. However by tilting by a small amount the axis 39, about whichthe arm 37 pivots, it can be arranged that the bush twister 40 rotatesabout an axis inclined to the horizontal by a small angle, so that theyarn path before and after the bush twister can then be vertical.

In the embodiment shown in FIGS. 3 and 4 the axes of rotation of thebush twister 40 and the wheel members 48 are horizontal, but they may beinclined at a small angle to the horizontal as above mentioned, whereasthe axis of rotation of the cup-like driving wheel is vertical andtherefore transverse to the axes of the bush twister and the wheelmembers. It will be appreciated, however, that the axis of rotation ofthe driving wheel need not be vertical, and that in some applications itmay be desirable for the driving wheel axis to be inclined to thevertical while still being transverse to the substantially horizontalaxes of the bush twister and the wheel members.

In the embodiment shown in FIGS. 1 and 2 the driving wheel rotates abouta horizontal axis, and as previously stated its shaft is rotated bymeans of a belt of which the plane of travel is horizontal. Theembodiment of FIGS. 3 and 4 can however be readily fitted to existingtextile false twist crimping machines, designed to have false twistingspindles driven from belts of which the plane of travel is vertical.

The driving wheel 42 could drive more than one bush twister 40, forexample two bush twisters could be driven by the driving wheel.

Prior art bearing-mounted bush twisters have been very limited as torotational speed and therefore yarn processing speed, and also as todurability. With a driving and supporting arrangement for a bush twisteraccording to the present invention considerably higher rotational speedscan be attained. The useful life is also considerably increased.

We claim:

1. In an apparatus for false-twisting of yarn and the like, incombination, rotatable drive wheel means having a periphery;bush-twister means for false-twisting a yarn travelling through saidbush-twister means; mounting means mounting said bush-twister means withfreedom of rotation; and holding means for holding said bush-twistermeans in frictional driving engagement with said periphery of said drivewheel means, whereby said bush-twister means is rotated in response torotation of said drive wheel means.

2. In an apparatus as defined in claim 1, said holding means comprisingat least a pair of wheel members freely rotatable about respectiveparallel axes.

3. In an apparatus as defined in claim 2, wherein each of said wheelmembers comprises at least two discs mounted for rotation about a commonaxis.

4. In an apparatus as defined in claim 2, said mounting means comprisinga mounting arm mounting said wheel members thereon.

5. In an apparatus as defined in claim 4; and further comprising pivotmeans mounting said arm for pivotal movement about a fixed axisparalleling said respective parallel axes and the axis of rotation ofsaid bushtwister means.

6. In an apparatus as defined in claim 5; and further comprising biasingmeans resiliently biasing said arm about said fixed axis in directiontowards said axis of rotation of said bush-twister means.

7. In an apparatus as defined in claim 3, each of said discs having aperiphery; and further comprising an annulus of wear-resistantfriction-promoting material encircling the peripheries of the respectivediscs.

8. In an apparatus as defined in claim 1, said holding means comprisingwheel means, and said wheel means and bush-twister means each alsohaving respective peripheries; and further comprising annular means ofwear-resistant friction-promoting material encircling at least one ofsaid peripheries.

9. In an apparatus as defined in claim 8, wherein said material ispolyurethane.

10. In an apparatus as defined in claim 8, wherein said annular means isprovided on and encircles at least an additional one of saidperipheries.

11. In an apparatus as defined in claim 8, wherein said annular means isprovided on and encircles all of said peripheries.

12. In an apparatus as defined in claim 2; further comprising a rotaryshaft mounting said drive wheel means and being rotatable about an axisparalleling said respective parallel axes and the axis of rotation ofsaid bush-twister means.

13. In an apparatus as defined in claim 12, said drive wheel meanscomprising a disc-shaped drive wheel whose general plane extends normalto the axis of rotation of said rotary shaft.

14. In an apparatus as defined in claim 2; further comprising a rotaryshaft mounting said drive wheel means and being rotatable about an axisextending transversely to said respective parallel axes and the axis ofrotation of said bush-twister means.

15. In an apparatus as defined in claim 14, said drive wheel meanscomprising a cupped rotor having an axially directed rim whichconstitutes said periphery.

16. In'an apparatus as defined in claim 1; further comprising magnetmeans acting upon said bush twister means for preventing displacementthereof in direction of the axis of rotation of said bush-twister means.

17. In an apparatus as defined in claim 1; further comprising arotatable drive shaft mounting said drive wheel means for rotation; anda pulley mounted on said drive shaft and having a circumferentialsurface adapted to have yarn being false-twisted convoluted thereaboutso as to effect advancement of the yarn through said bush-twister means.

i i i f

1. In an apparatus for false-twisting of yarn and the like, incombination, rotatable drive wheel means having a periphery;bush-twister means for false-twisting a yarn travelling through saidbush-twister means; mounting means mounting said bushtwister means withfreedom of rotation; and holding means for holding said bush-twistermeans in frictional driving engagement with said periphery of said drivewheel means, whereby said bushtwister means is rotated in response torotation of said drive wheel means.
 2. In an apparatus as defined inclaim 1, said holding means comprising at least a pair of wheel membersfreely rotatable about respective parallel axes.
 3. In an apparatus asdefineD in claim 2, wherein each of said wheel members comprises atleast two discs mounted for rotation about a common axis.
 4. In anapparatus as defined in claim 2, said mounting means comprising amounting arm mounting said wheel members thereon.
 5. In an apparatus asdefined in claim 4; and further comprising pivot means mounting said armfor pivotal movement about a fixed axis paralleling said respectiveparallel axes and the axis of rotation of said bush-twister means.
 6. Inan apparatus as defined in claim 5; and further comprising biasing meansresiliently biasing said arm about said fixed axis in direction towardssaid axis of rotation of said bush-twister means.
 7. In an apparatus asdefined in claim 3, each of said discs having a periphery; and furthercomprising an annulus of wear-resistant friction-promoting materialencircling the peripheries of the respective discs.
 8. In an apparatusas defined in claim 1, said holding means comprising wheel means, andsaid wheel means and bush-twister means each also having respectiveperipheries; and further comprising annular means of wear-resistantfriction-promoting material encircling at least one of said peripheries.9. In an apparatus as defined in claim 8, wherein said material ispolyurethane.
 10. In an apparatus as defined in claim 8, wherein saidannular means is provided on and encircles at least an additional one ofsaid peripheries.
 11. In an apparatus as defined in claim 8, whereinsaid annular means is provided on and encircles all of said peripheries.12. In an apparatus as defined in claim 2; further comprising a rotaryshaft mounting said drive wheel means and being rotatable about an axisparalleling said respective parallel axes and the axis of rotation ofsaid bush-twister means.
 13. In an apparatus as defined in claim 12,said drive wheel means comprising a disc-shaped drive wheel whosegeneral plane extends normal to the axis of rotation of said rotaryshaft.
 14. In an apparatus as defined in claim 2; further comprising arotary shaft mounting said drive wheel means and being rotatable aboutan axis extending transversely to said respective parallel axes and theaxis of rotation of said bush-twister means.
 15. In an apparatus asdefined in claim 14, said drive wheel means comprising a cupped rotorhaving an axially directed rim which constitutes said periphery.
 16. Inan apparatus as defined in claim 1; further comprising magnet meansacting upon said bush twister means for preventing displacement thereofin direction of the axis of rotation of said bush-twister means.
 17. Inan apparatus as defined in claim 1; further comprising a rotatable driveshaft mounting said drive wheel means for rotation; and a pulley mountedon said drive shaft and having a circumferential surface adapted to haveyarn being false-twisted convoluted thereabout so as to effectadvancement of the yarn through said bush-twister means.